1. Field of the Invention
The present invention relates to a method and apparatus for recording/reproducing data, and more particularly to a method and apparatus for encoding/decoding data, and a method and apparatus for recording/reproducing data using the encoding/decoding method.
2. Discussion of the Related Art
An apparatus (e.g., a compact disc (CD) or a digital versatile disc (DVD)) for recording/reproducing information or data in/from a recording medium can record information or data in a single-layered record surface, and can reproduce the information or data recorded in the single-layered record surface.
If the above-mentioned recording/reproducing surface of the recording medium is configured in the form of a laminated structure, storage capacity of the recording medium can be greatly increased. However, the number of the recording/reproducing surfaces capable of being laminated on the single recording medium is generally set to a maximum of 4, so that there is a limitation in increasing the storage capacity of the recording medium.
Due to the above-mentioned limited storage capacity of the recording medium, many developers are conducting intensive research into a new technology for increasing the storage capacity of the recording medium using holography.
The holography is indicative of a technology for reconstructing a light signal without any change. The holography can store an interference pattern, which is formed by both a target light including necessary information and a reference light received at an angle different from an angle of the target light, in the recording medium, or can reproduce information of the recording medium using a diffraction of the stored interference pattern.
In the case of using the above-mentioned holography-based storage technology, the interference pattern can be three-dimensional and overlapped in a direction of the recording-medium thickness so that the storage capacity of the recording medium can be greatly increased.
In other words, if data is recorded in the recording medium simultaneously while changing an incident angle, phase, and wavelength of the reference light, a plurality of holography information pieces can be recorded in a predetermined storage capacity. As a result, a recording medium with great storage capacity can be implemented.
In addition, a light signal and a recording light signal can be scanned on the recording medium using a beam splitter and an objective lens, so that an apparatus for recording/reproducing data in/from the recording medium (also called an optical recording/reproducing apparatus) can be configured in the form of a small-sized structure.
However, if an incident angle of the reference light signal is incorrect in a conventional optical recording/reproducing apparatus using the holography, many interferences are generated between recorded data pieces or reproduced data pieces.
For example, if data of the recording medium is reproduced, the incident angle of the reference light signal must be equal to that of the recording light signal. Provided that the incident angle of the reference light signal is not equal to that of the recording light signal, data recorded in the recording medium may be incorrectly recovered.
In order to correctly record or recover the data of the recording medium, a data encoding/decoding process for recording/reproducing data is a mater of great importance. Specifically, there is needed a new algorithm capable of correcting errors generated by the encoding/decoding process and correctly encoding/decoding data.